Cylindrical weights Shape, constituent material and method of manufacture Cylindrical shape with a flat knob for gripping. Material used : any material with a density of 7 to 9 75 g/cm3, of a hardness at least equal to that of cast brass, not less resistant to corrosion and not more friable than grey cast iron, and with a surface comparable to that of grey cast iron carefully cast in a mould of fine sand. Grey cast iron may not be used for weights of a nominal value of less than 100 g. The method of manufacture to be appropriate to the material chosen.
